Enabling FuzeDrive in Windows Recovery and Windows PE Environments and Repairing BCD

Enabling FuzeDrive in Windows Recovery and Windows PE Environments and Repairing BCD


The following article provides manual steps for enabling FuzeDrive in a typical Windows recovery (or PE) environment. It also addresses the situation when the BCD (EFI) or legacy boot configuration are no longer functioning correctly for your bootable FuzeDrive, or when your Windows system files are corrupted.

Note: If you cannot boot after updating your BIOS, your settings may have been reset to defaults.  In this case, make sure Secure Boot is off and that SATA AHCI mode (rather than RAID) is selected.  Also, ensure NVMe RAID is disabled if you are using an NVMe in your tier.

The reader is encouraged to also consult Microsoft or other third party documentation on recovering Windows as there may be many reasons a Windows system may no longer boot properly.

This is an expert guide and requires a high level of proficiency in Windows command line and disk volume environments.

STEP 1a: If you are booting to the built-in Windows recovery environment (i.e., not an install or recovery USB), then the driver should already be installed.  If Windows Recovery loads automatically and you were NOT asked to "Choose your keyboard layout": Choose Troubleshoot > Advanced options > Command Prompt to get to a command line window.  If you are in UEFI boot mode, skip to step 8 below in the section "Mount the FuzeDrive EFI Partition," or skip to the section "Legacy MBR Boot Drive Windows Recovery" otherwise.

STEP 1b: If you instead booted from a Windows install/recovery USB, or if Recovery booted automatically but you were asked to "Choose your keyboard layout", then continue to step 2.

Copy Driver Files to USB Device

STEP 2: From another computer, download the ZIP file attached to the bottom of this article, and unzip it to a USB stick.

EFI Boot Drive Windows Recovery (or Win PE Environments):

STEP 3: Navigate to the Troubleshoot, Advanced options, Command Prompt to get to a command line window.

STEP 4: Plug in the USB key. This will be assigned it’s own drive letter, C: or D:, etc.

STEP 5: Determine which drive letter the USB key was assigned. The simplest method is, at the command prompt, type:

               > C:
               > dir

If the virtahci7 and virtahci8 directories are listed, continue to step 6a. If they're not present, enter D: then dir. Continue up the alphabet until you find the directories. Alternatively, you can enter diskpart and list vol to see which volumes are visible, then exit, and enter the appropriate drive letter.

STEP 6a: For Windows 8 or 10 enter:
               > cd virtahci8

STEP 6b:
 For Windows 7 enter:
               > cd virtahci7

STEP 7: Load the Enmotus driver by typing the following:
               > cd virtahci8

               > drvload envirtahci.inf

Wait up to 20 seconds for the driver to load and mount new volumes.  If the FuzeDrive NTFS file structure is intact, a new drive letter will have been added (D: or E:, etc.).  If not, then the FuzeDrive may not be able to load.

Mount the FuzeDrive EFI Partition

If your Windows was installed in Legacy (MBR) mode, skip to the "Legacy MBR Boot Drive Windows Recovery" section below.

STEP 8: Enter the following:
               > C:
               > dir

If you do not see the contents of your former C: drive, enter D: then dir.  Continue up the alphabet until you find your Windows boot drive.  If you cannot find your Windows boot drive, go to the "Cannot Find Windows Partition" section below.

STEP 9a: If you did not have to do the procedure in steps 2-7 to load the driver, mount the EFI partition by typing the following:

               > mountvol s: /s

If the command does not report an error, go to step 12a below.

STEP 9b: If you followed steps 2-7, or if step 9a reported an error, then enter the following commands:

            DISKPART> diskpart

DISKPART> list vol

You should see something like the following:

DISKPART> list vol

  Volume ###  Ltr  Label          Fs         Type             Size         Status       Info

  Volume 0       C     Windows    NTFS   Partition      1046 GB  Healthy    

  Volume 1                Recovery    NTFS   Partition       450 MB  Healthy    

  Volume 2               SYSTEM     FAT32  Partition      100 MB   Healthy   Hidden  

  Volume 3        D     DRIVER      FAT32  Removable     14 GB  Healthy

STEP 10: Identify the EFI System Partition. This is typically the 100MB FAT32 volume labelled “SYSTEM” or "ESP".  If you do not see a FAT32 volume of 100-500MB, enter list disk.  If you do not see the last "Gpt" column with a * next to your FuzeDrive.  To identify your FuzeDrive disk, use the "Size" column, or enter sel disk 0 or sel disk 1, etc. then detail disk and look for "T00 FuzeDrive."  If there is no *, then you are in Legacy boot mode, so skip to the "Legacy MBR" section below.  If your FuzeDrive did not mount successfully, skip to "If All Else Fails" at the end of the article.

STEP 11: Assign the EFI partition a volume by typing the following (assumes your EFI System Partition is vol 2, as our example above):

               DISKPART> sel vol 2

               DISKPART> assign letter=S

               DISKPART> exit

Repairing the Microsoft Boot Record and BCD store

STEP 12a: Change to the S: EFI volume and repair the boot record:

               > cd /d s:\efi\microsoft\boot

               > ren bcd bcd.old

               > bootrec /fixboot

               > bootrec /rebuildbcd

               [enter Y when prompted]

Reboot.  Hopefully this has fixed your boot issue. If not, repeat the steps above and continue to step 12b.

STEP 12b: If bootrec is not recognized as a valid command, or if step 12a did not work, then, assuming drive D: is your Windows partition, after renaming the BCD file, enter:

                > bcdboot d:\windows /s s:

Reboot and try again.  If the boot issue is not resolved, skip to the "Other Troubleshooting" section below.

Legacy MBR Boot Drive Windows Recovery (or Win PE Environments):

If your Windows was installed in legacy MBR mode, follow steps 1-7 above, then:

STEP 8a (legacy): Fix the boot record and boot tables using the following commands:

               > bootrec /fixmbr

               > bootrec /fixboot

STEP 8b (legacy): Fix the boot record and boot tables using the following commands:

               > bootrec /fixmbr

               > bootrec /fixboot

If you get a "multiple indistinguishable devices" error, you will need to change the GUIDs of the FuzeDrive EnTier EFI System Partitions for bootrec to find the proper ESP on the tier.
To do so, enter:
               > bootrec /fixmbr
               DISKPART> list vol
Look for two 3MB partitions. They may be labelled "EnTier_ESP". Select one of them, e.g. if one is volume 2:
               DISKPART> sel vol 2
               DISKPART> help set id
Copy the last line, then paste it with the middle mouse button, i.e.:
               DISKPART> SET ID=ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
Select the other volume and paste the SET ID line again.

Windows System File Troubleshooting:

STEP A: If your FuzeDrive mounted successfully, if your boot issue is not resolved, then assuming your original C: drive is mounted to drive D:, try the following command:
               > sfc /scannow /offbootdir=d:\ /offwindir=d:\windows

STEP B: If that doesn't fix your issue, then assuming your original C: drive is mounted to drive D:, you can try:
               > dism /image:d:\ /cleanup-image /restorehealth

STEP C: If Windows still won't boot, then you can reinstall Windows while keeping your documents safe by choosing TroubleshootReset this PC > Keep my files.

Cannot Find Windows Partition:

STEP A: Enter the following:

            DISKPART> diskpart

DISKPART> list disk

STEP B: Check the sizes of the disks.  Is there a drive of the right size to be the FuzeDrive?  You can enter sel disk 0 then detail disk and look for "T00 FuzeDrive" to be sure.  Keep looking with sel disk 1 then detail disk, etc.  If you checked all your disks and there is no FuzeDrive, skip to "If All Else Fails" below.  If you did find the FuzeDrive, enter:
            DISKPART> exit

            > mountvol

You will see something like the following:

X:\> mountvol

    *** NO MOUNT POINTS ***



STEP C: To attempt to fix a potentially broken filesystem on a Windows volume, enter:
            chkdsk /f \\?\Volume{12345678-1234-1234-1234-123456789abc}

[where the volume is one that has no mount points, and the backslash at the end has been removed.]

Repeat step C for other unmounted volumes as necessary.

If All Else Fails:

If the FuzeDrive did NOT mount successfully, or the Windows volume is still missing, then to troubleshoot further you will need to install Windows to a third disk, or move your 2 FuzeDrive disks to another PC, install FuzeDrive on the new/other Windows installation, and open a ticket with Enmotus support for assistance.
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